class Container {
    static of(value) {
      return new Container(value)
    }
    constructor(value) {
      this._value = value
    }
    map(fn) {
      return Container.of(fn(this._value))
    }
  }
  class Maybe {
    static of(value) {
      return new Maybe(value)
    }
    isNothing() {
      return this._value === null || this._value === undefined
    }
    constructor(value) {
      this._value = value
    }
    map(fn) {
      return this.isNothing() ? this : Maybe.of(fn(this._value))
    }
  }
  module.exports = { Maybe, Container }